Would it be possible to run multiple instances of ipdf at once?
I would like to switch between 2 or even more documents. For example, one has the text, the other one the footnotes, or the pictures etc.

In the case of the iliad, the window manager is "matchbox". It has been configured so that it doesn't show titlebars; if you enable them, in the top-left icon of the window titlebar, matchbox shows a list of the running applications.

In the start.sh script, if you change the " -use_titlebar no " to " -use_titlebar yes ", you should have the matchbox titlebar for full-screen apps, including ipdf. Alas, modifying start.sh is very dangerous (you can make you iliad incapable of booting, so you should double-check that you can reflash from CF before attempting this).